Reconstructive bone and ligament surgery often involves drilling into skeletal members to attach connective elements such as ligament and tendon grafts, as well as various artificial replacements and/or attachments for articulated joints. In particular, reconstructive surgery involving the anterior cruciate ligament (ACL) is becoming particularly significant because the effectiveness of reconstruction can have a profound effect on the subsequent physical abilities of the patient. For professional athletes, for example, an effective ACL repair can salvage an otherwise career ending injury. Similarly, an improperly treated ACL injury can be a permanent detriment for even everyday mobility.
Surgical procedures for reconstructing ambulatory joints, such as an ACL or PCL (Posterior Cruciate Ligament), often involve drilling bone tunnels through the femur and/or tibia. In such a procedure, although the ACL is typically referred to as a single ligament, it consists of two functional bundles, named for attachment points on the tibia. An anteromedial (AM) bundle is located more anterior (towards the front) and medial (towards the inside) of the tibia. A posterolateral (PL) bundle connects most posterior (towards the back) and lateral (towards the outside) of the tibia. Reconstructive procedures may be single bundle, directed at replacing/reconstructing one bundle or may be a double bundle procedure, focused on replacing/reconstructing both the AM and PL bundle. Each bundle requires a respective bone tunnel to be drilled in the femur.